Refrigeration apparatus



Sept. 10, 1935. E, T, w A Re. 19,700

REFRIGERATION APPARATUS Original Filed Nov. 2'7, 1929 2 Sheets-Sheet 1 INVENTOR Sept. 10, 1935.

E. T. WILLIAMS REFRIGERAT I OH APPARATU 5 'original Filed Nov 27, 1929 7E Md 2 Sheets-Sheet 2 INVENTORY ATTORNEY Reiosued Sept. 10, 1935 UNITED STATES PATENT OFFICE Original No.

Serial No. 410,026, November 27, 1929.

1,947,574, dated February 20, 1934,

Reissue No. 19,595, dated May 28, 1935, Serial No. 754,123, November 19, 1934. This application for reissue July 17, 1935, Serial No. 31,940

45 Claims.

My invention relates to the art of refrigeration and particularly to refrigerating apparatus of the so-called compression type and still more particularlyto compression refrigerating appa- 6 ratus when used in connection with multiple installations.

This type of installation is used particularly in apartment houses where a refrigerator cabinet containing an evaporator is placed in each of a plurality of apartments and supplied with refrigerant from a single compressor and condenser. It is customary to place as many as thirty evaporators in a single system and hence the quantity of refrigerant contained in such a system is necessarily large. In systems used heretofore, if a leak occurred in one apartment, the entire contents of the system were free to escape through this leak, and this large quantity of refrigerant in a comparatively small apartment was dangerous and was apt to seriously affect the occupants. Even if a comparatively nonpoisonous refrigerant is used such as would not be injurious to life if present in small quantitles, such might escape from an individual refrigerating apparatus, such a refrigerant in large quantities has been found to be injurious.

One of the objects of my invention is to provide a multiple refrigerating system employing a smaller quantity of refrigerant for a given number of evaporator: than has heretofore been found possible. Another object is to provide safety devices whereby a leak at any point in the system will cause these safety devices to operate so as to isolate that portion of the system and. thus prevent the leakage of refrigerant from other parts of the system.

These as well as other'obiccts and advantages will be apparent from the following description taken in connection with the accompanying drawings which form a part of the specification and on which: I

Fig. 1 is a more or less diagrammatic view of a preferred embodiment of my invention;

Fig. 2 is a crosssectional view of a solenoid valve used in connection with my invention;

Fig. 3 is a cross-sectional view of. a one-way check valve;

. Fig. A is a cross-sectional view of a pressureresponsive electric switch; and

Fig. 5 is a cross-sectional view of another type of pressure-responsive electric switch.

Referring more particularly to Fig. 1, reference character indicates a compressor which is operatively connected to an electric motor II and driven thereby. A conduit 12 connects the discharge port of compressor 10 with a suitable condenser II .which may be cooled in any desired way, as by air or water. A conduit l4 connects the lower part of condenser i3 with a receiver ii. A conduit l6 communicates with re- 5 ceiver I5 at such a level that approximately two pounds of refrigerant may be contained in the receiverbelow this level. The other end of conduit i8 communicates with an auxiliary receiver 22. A conduit 23 communicates with the bottom of receiver IS. A conduit 25 connects the bottom of the lower part oi' auxiliary receiver 22 with conduit 23 and is provided with a manually operable valve 26. A similar valve 21 is placed in conduit 23 between receiver l5 and the point of communication of conduit 25 therewith. A conduit 30 connects the upper part of receiver IS with auxiliary receiver 22 and is provided with a valve 33. A float chamber 2| is placed adjacent to the lower part of receiver ii and connected thereto by means of conduits 20 and 2| as shown. Within float chamber 24 is a float 34 pivotally connected to an arm I! which is pivoted at It. Secured to arm I5 is a plate 31 to which is attached a bellows member #0. The other end of bellows 40 is secured to float chamber 24. This arrangement allows a limited movement of arm 35 about point 36, while providing a perfect seal. On the outer end of arm I! is mounted a mercroid switch 4| arranged so that the electric circuit therethrough will be closed when float It is in raised position. Secured to arm. at 42 is a tension spring 0, the other endof which is secured to float chamber 24 at ll. The purpose of this spring is to tend to hold arm 35 in an extreme 35 raised or lowered position, but when the force of this spring is overcome by float 34 and arm 85 passes "dead center", the spring quickly snaps the arm into the opposite extreme position and thus quickly either opens or closes mercroid switch ll. Conduit It connects receiver it with solenoid valve 46, which valve is shown in detail in Fig. 2. Valve 48 comprises a housing Ill across which is formed a partition III. A valve seat I4} is formed in partition Ill. A valve member I is slidably mounted in a cylindrical member "5 and is forced downwardly to engage seat I by a spring I". Valve member I, or at least the pper part thereof, is made of magnetic material and around the outside of member I" is placed 50 a magnetic coil I41. Thus,-when current is supplied to coil ill the resulting magnetic force will act to move valve member I upwardly against the force of spring I and thus open the valve.

When the supply of current fails, the spring will apartments.

seat valve member I44 which prevents the passage of fluid through the valve.

A conduit 41 connects the other end of valve 46 with a high side header 60. Connected to header 50 are conduits 5|, 52, and 53. Placed in each of these conduits are check valves 64, 55, and 56, respectively. These valves are of similar construction and are shown more in detail in Fig. 3, and comprise a seat I50 upon which a valve plate I5I is arranged to be seated by gravity. Above seat I50 are a number of projections or stops I52 which limit the upward movement of plate I5I. In operation fluid tending to pass upwardly through the valve will raise plate I5I against the action of gravity and pass around the valve. However, fluid tending to pass in the opposite direction will force plate I5I against seat I50 and thus the valve will be closed.

Conduits 5|, 52, and 53, which may be referred to as riser conduits, extend to the evaporators placed in refrigerator cabinets in the various The number of riser conduits depends on the number and arrangement of apartments to be served by a single system and there are here shown three riser conduits, each serving three apartments. As the apparatus con nected to each riser conduit is similar, only that connected to a single riser conduit will be described.

Connected to riser conduit M are conduits 51, one for each refrigerator served by this riser.

Placed in conduits 51 are check valves 60, similar I to the valve shown in Fig. 3. Conduits 6| connect the other end of these valves to evaporators 62, which are placed in suitable refrigerator cabinets. Connected to the outlets oi evaporators 62 are return conduits 03 which communicate with a low side header 63. Placed in each conduit 63 is a check valve 64, similar to the valve shown in Fig. 3. It is necessary to form conduits 6'3 with a return bend in order that valves 64 shall be in the proper position, as to function properly the flow therethrough must be upwardly.

Similar low side headers 65 are provided for the return conduits from the evaporators served by riser conduits 52 and 53, respectively. A conduit 61 is connected to low side headers 68, 65, and 66 by branch conduits I0, 1| and 12, respectively. In each branch conduit is placed a solenoid valve 13, 14, and 15, respectively. These valves are all similar to the valve shown in Fig. 2. Connected to conduit 61 by means of a branch conduit 16 is a pressure-responsive switch 11, which is shown in detail in Fig. 5.

Switch 11 comprises a bellows contained within a housing 80a to which is connected conduit 10, so that the pressure existing within the conduit will be communicated to the bellows. Pivoted within the casing 01' the switch is a bell crank lever 6|, the vertical arm 01 which is acted upon by member 02 actuated by bellows 00. A spring 00 tends to move the vertical arm in a counter-clockwise direction about its iulcrum, which movement is resisted by member. Secured to the horizontal arm of bell crank lever 8| at 84 is astrip of resilient metal 85 which in this switch lies flat ori-the horizontal arm. Secured to the other end. of strip 85 is a rod 86, the other end of which is connected to a switch arm 90. In this switch strip has no utility and hence might be omitted and rod 06 connected directly to lever 0|. However, this is a standard switch and in a difl'erent embodiment, to be described later, the strip is required. Ann 80 is pivoted at one end at 0| and is provided near its other end with a contact 02. Arranged below contact 02 is a similar stationary contact 00. A compression spring I40 tends to force arm 00 downwardly and keep contacts 92 and 00 together. Pivoted in the casing of the switch at 04 is a catch 05, one end of which projects through an opening in the casing. The other end of catch 05 bears against the end of the horizontal portion of hell crank lever BI when that end is in its lowermost position. A spring 06 is arranged to force catch 95 against the bell crank lever, and when the lever is raised the lower end of catch 05 slips under the lever and prevents it from returning toits lowermost position until the catch has been released by hand.

The operation of this switch is as follows: Spring 03 tends to rotate bell crank lever 0| in a counter-clockwise direction. This motion is resisted by member 02, which is attached to bellows 00. As long as the pressure within bellows B0 is suiilcient to overcome the force of spring 83, the lever will remain in the lowermost position. However, if the pressure within the bellows decreases. spring 83 will be able to move bell crank lever M,

which will cause rod 00 to be moved upwardly, to

the position shown, thus pivoting switch arm 90 in a clockwise direction. This will cause con tacts 92 and 00 to separate against the force of spring I40, thus opening the circuit through the switch. When lever BI is moved to the upper position catch 06 slips under the end of the lever, as shown, and prevents the lever being moved to its lower position. Hence, even though the pressure in bellows 00 should subsequently increase, it will be unable to re-close the switch due to catch 95,

until this catch has been released by hand.

Conduit 61 communicates with a pressure-responsiveswitch I00 of any suitable type which is designed to open the electric circuit therethrough at a predetermined low pressure and to close the of which is mounted a bellows I01 within a hous- D ing I010, which is connected to conduit I04. A similar bellows I I0 is mounted within a housing ll0a. on the other side of the casing and is likewise connected to conduit I04. Switch I05 is similar in some respects to switch 11, but embodies additional features which causes the switch to open at high pressures as well as low pressures. The additional features comprise bellows H0 which actuates a member III which in turn actuates a bell crank lever II2 pivoted at I I3. A tension spring I tends to rotate lever I I2 in a counter-clockwise direction. Lever H2 is connected to a snap action mechanism H0 by means of a link H6. Mechanism H5 is provided with a pro- Jection .I I1 arranged to strike the lower side of switch arm 00 and raise the arm and thus separate the contacts 02 and 93. A loosely mounted pin I20 projects through the back of casing I06 and is provided with a spring which tends to force it against bell crank lever II! when the switch is in closed position.

The operation 01' this switch is as follows: The operation of bellows I01 In opening the? switch is exactly the same as was described in connection with the switch shown in Fig. 5, and therefore need not crank lever 0|.

repeated here. when the pressure in bellows III increases sufliciently, it rotates bell crank lever H2 in a clockwise direction against the force of spring III. .This movement of bell crank lever 2 causes the snap action mechanism II! to be moved into the position shown, and projection II'I strikes switch arm 00 and raises the arm. This, of course, causes rod 00 to be raised, but does not affect the position of hell crank lever 0| due to the resilient connection furnished by strip 00 between rod 06 and bell When bell crank lever H2 is moved to this position by bellows IIO, pin I20 is able to pass the lever and thus the lever cannot be returned to its original position by spring I if the pressure in bellows IIO should drop. In order to return bell crank lever II2 to its original position and thus close the switch, it is necessary to manually pull pin I20 out, whereupon lever I I2 will return to its original position and member I20 will be held outwardly by bearing against the lever in this position.

The electric circuit for controlling the above described refrigerating system is as follows: Electric current at suitable voltage is supplied to leads HI and I22 through aswitch I22. Lead I22 is connected to one terminal of pressure-responslve switch I00. The other terminal of switch I00 is connected by a conductor I20 to one terminal of motor II. Lead I2I is connected to one terminal of switch I00, the other terminal of which is connected by means of a conductor I25 with one terminal of mercroid switch ll. The other terminal of mercroid switch ll is connected by conductor I24 with one terminal of switch II, the other terminal of which is connected by means of a conductor. I26 with motor II. Connected in parallel withswitches ll, I00 and I1 is an electric relay I21, thewindings of which have a comparatively high resistance so that the relay will not be actuated when the circuit through the three switches is closed, but will be actuatedwhen any one of the switches opens. The resistance of the windings of relay I21 is great enough so that sufllcient current cannot pass therethrough to actuate motor II or hold any of the solenoid valves open. Relay I2! is arranged to close a circuit through an alarm bell I20 or the like whenever the relay is actuated. Solenoid valves II, II, I! and I02 are connected to a circuit comprising conductors I20 and III. Conductor I20 is connected to conductor I20, while conductor III is connected to conductor I22. Thus it will be seen that current will be supplied to the circuit comprising conductors I20 and III regardless of whether or not switch I00 is open or closed. but current will not be supplied to this circuit if switches 4|, I00, "or any one of them is open. Solenoid valve 40, on the other hand, is connected by conductors I20 and III to conductors I22 and I20. respectively, and hence this valve is closed whenever any one of switches II, I00, ll or I00 is open.

The operation of the refrigerating system as a whole is as follows: Assume that methyl-chloride, or a similar fluidis the refrigerant employed. The system is charged with this refrigerant and approximately two pounds are contained in receiver I0. Anything in excess thereof will pass through conduit I0 into auxiliary receiver 22. In operation, valve 21 is open, valve 20 is closed and valve 00 is open. The vaporous refrigerant is compressed by compressor I0 and passes through conduit I2 to condenser I2, where it is liquefied due to cooling action. The liquid refrigerant passes through conduit I4 to receiver IS and from the receiver through conduit 22 valve 40 and thence through conduit 41 to header 00. From header 00 liquid refrigerant passes through riser 5 conduits 0|, 52, and 50, and check valves 54, 00, and 08, respectively, to the various evaporators. Following the liquid through the evaporators served by riser II, it passes through conduits Bl, check valves 60 and conduits BI to the evaporators 02 of this section. In the evaporators the pressure of the liquid refrigerant is reduced by passing through a suitable valve. The lower pressure in the evaporators causes the refrigerant to evaporate. This evaporation requires heat, which is absorbed from the contents of the interior of the refrigerator cabinet within which evaporators 02 are placed. The vaporaus refrigerant thus produced in evaporators 02 passes therefrom through conduits 63 and check valves 64 to header 20 08. From header 60 thevaporous refrigerant is drawn through valve I3, conduits I0 and 61, switch I00, conduit IOI, valve I02 and conduit I00, to compressor I0, thus completing its cycle. The refrigerant supplied to risers 02 and 50 passes 2 through the evaporators supplied by these risers and returns to headers N and 86, respectively, and thence passes through conduits II and 12, respectively and valves" and I0, respectively, to conduit Ill.

The temperature maintained in the evaporators is a function of the pressure, existing therein. The lower the pressure, the lower the corresponding temperature. Hence, this pressure'may be utilized to control the operation of the compressor and thus the desired temperature maintained in the evaporators; For this purpose pressure-responsive switch I00 is provided and, for methyl-chloride, is adjusted to open the electric circuit and thus stop'motor II, and close valve 40 40 when the pressure has been reduced to betweenslx and ten pounds in the evaporators 02, and to close the circuit and start motor II and open valve 48 when the pressure in the evaporators has increased to approximately twenty pounds. Valve 28 is closed each time the motor is stopped in order to prevent surging in the system. Surging would occur if several evaporator valves happened to be open, when the compressor stops as under these conditions no refrigerant is being supplied to receiver I! but the receiver would continue to supply refrigerant to the evaporators the val es of which are open, if valve 40 were not closed. Ifsuch surging was permitted, a much larger receiver would be required to contain enough refrigerant to take care of the surge and hence a larger quantity of refrigerant would be present to escape in case of a leak.

Assume now that a leak occurs at the point marked "a" in conduit n. This leak will allow liquid refrigerant contained in receiver II, con duit 22, float chamber 24, conduits l0 and 41, header 00 and conduit 0| to start to escape. The contents of the other risers I2 and 02 cannot reach this leak due to the check valves 00 and 00, which prevent flow from the risers into header 00. Likewise the contents of evaporators served by riser II cannot reach the leak at A" due to the check valves 00. The leak at "A will allow 7 the pressure in the high side of the system back to the compressor to fall. This reduced pressure will be communicated through conduit I0! to pressure-responsive switch I00. The reduced pressure in bellows ill will cause switch III to 76 be opened. Or it mayhappen that sufficient refrigerant will escape from reseiver I and float chamber 24 to allow float 34 to drop and open switch 4| before the pressure is reduced sufflclently to actuate switch I05. The opening of switch U or I05 will open the circuit comprised of conductors I30 and I3I, which will cause solenoid valve 46 to close, thus isolating the leak between valve 46 and check valves 60. This will occur before a sufficient quantity of refrigerant has escaped to be injurious to persons occupying the apartment in which the leak occurs. The opening of switch I05 or 4I will also open the motor circuit and stop the compressor and also cause bell I28 to ring, which will give immediate warning of the leak.

Next assume a leak to occur in one of the return conduits, for instance, conduit 63 at "B. The pressure within this conduit is between six and twenty pounds gauge, wherefore vaporous refrigerant will escape through the leak. Leakage at this point will continue at a comparatively slow rate until suiiicient refrigerant has leaked from the system to either reduce the pressure obtaining in the high side sufficiently to open switch I05, as occurred in the previous case, or to reduce the quantity of liquid refrigerant in the high side sufficiently to allow float 34 to drop and thus open mercroid switch 4|. Either or both of these switches will open before a dangerous amount has escaped at B. Upon the opening of either of these switches the motor will be stopped and solenoid valves 46, I3, II, I2 and I02 will be closed. The leak will thus be isolated between valve 46 and check valve 64 in conduit 63. Check valve 64 will prevent the passage upwardly through conduit 63 of refrigerant in header 63 and of refrigerant supplied to the header by the other return conduits 63. Likewise, in this case, the bell I28 will ring as soon as either switch II or I05 is opened and thus give warning that a leak has occurred.

Next assume a leak to occur at "C" in conduit BI. If methyl-chloride is the refrigerant employed, the pressure within conduit 61 will be between six and twenty pounds and will. of course, drop to zero pounds gauge when the leak occurs. This will immediately cause pressure responsive switch 11 to open, as this switch is adjusted to open at a pressure just above zero pounds gauge, say, approximately, at one pound. The opening of switch 11 will open the motor circuit, thus stopping the motor, and will also open the circuit comprised of conductors I30 and I3I, which will cause the solenoid valves to close. The leak at "C" will then be isolated between solenoid valves I3, I4, I5 and I02, and the amount of refrigerant which will have escaped will be negligible. The opening of switch 11 will cause bell I28 to give warning of the leak.

Switch I05 is arranged to open upon the occurrence of an abnormal pressure in the high side as well as in case of a subnormal pressure so that a dangerously high pressure may not be built up therein. Such a pressure might result from several causes, such as the failure of valve 4'3 to open when the motor starts or a failure of cooling water in case the condensenis water cooled.

Excess refrigerant placed in a system when initially charged will pass through conduit- I5 to auxiliary receiver 22, where it will remain as it cannot flow back intocirculation as long as valve 26 is closed. The provision of auxiliary receiver 22 prevents an excessive quantity of present in receiver I5, a leak will cause the high 5 side pressure to drop rapidly and thus cause switch I05 to open and of course float chamber 24 will become emptied much sooner with a small quantity of liquid in the receiver I5 than it would if a larger quantity were present. In case a leak occurs and is repaired, any excess refrigerant in auxiliary receiver 22 may be introduced directly into the receiver IE to make up for refrigerant lost through the leak by a proper manipulation of the manually operable valves. To do this, valve 28 should be opened and valve 21 closed. Liquid refrigerant contained in receiver 22 will then pass through conduit 25 into conduit 23. When all of the liquid refrigerant has been thus forced out of auxiliary receiver 22, the valves are returned to their former position and liquid refrigerant supplied from receiver I5 through conduit 23. Valve 26 may be provided with a look so that it may be opened and refrigerant introduced into the circulating system only by a duly authorized person.

I have shown and described a system employing pressure control of the compressor. With such control I prefer the use of float valves for regulating the supply of liquid refrigerant to the 30 evaporators. My safety system is equally applicable to other regulation combinations and is independent of the normal control of the refrigerating system. My safety arrangements may be used on a system employing pressure operated expansion valves to control the supply of refrigerant to the evaporators or expansion valves operated by a plurality of impulse sources. With expansion valves of the last mentioned types, thermostatic control of the motor may be used instead of pressure control.

While I have shown a more or less specific embodiment of my invention, it is to be understood that this has been done for purposes of illustration and that the invention is not limited thereto. It will be evident that parts of the system which I have shown may be used separately. Other refrigerants than those described may be employed and their use in combination with such a system falls within thescope of the invention, which is to be limited by the appended claims viewed in the light of the prior art.

What I claim is:

1. A refrigerating system comprising a compressor, a condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means and automatic means for dividing said system into isolated sections operable upon the occurrence of abnormal change in pressure at any point in the system.

2. A refrigerating system, comprising a compressor, a. condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means, valves in said conduits and pressure-responsive means operable upon the reduction of pressure within said system resulting from a leak in said system for closing said valves to divide said system into isolated sections.

3. A refrigerating system comprising a compressor, a condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means, valves in said conduits and licuid level responsive means operable upon the reduction of the quantity of liquid refrigerant contained within said system resulting from a leak in said system for closing said valve to divide said system into isolated sections.

4. 'A refrigerating system comprising a compressor, acondenser, evaporation means, conduits connecting said compressor, condenser and evaporation means, valves in said conduits and pressure-responsive means operable upon the increase of pressure within said system for closing saldvalves to divide said system into isolated sections.

5. A refrigerating system comprising a compressor, a condenser, an evaporator, means including a conduit for supplying said evaporator with liquid refrigerant from said condenser, a one-way valve in said conduit adi acent said evaporator, means for conveying vaporous refrigerant from said evaporator to said compressor, a second valve in said conduit and means for closing said second valve when the pressure in said conduit is below normal.

6. A refrigerating apparatus comprising a compressor, a condenser, a receiver, an evaporator, means including a conduit for supplying said evaporator with liquid refrigerant from said receiver, a one-way valve in said conduit adjacent said evaporator, means for conveying vaporous refrigerant from said evaporator to said compressor, an electrically actuated valve in said conduit and means including a float operated switch responsive to the liquid level in said receiver for closing said valve.

'l. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduitfor supplyingsaid evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves, when the pressure in said first conduit is below normal.

8. A refrigerating apparatus comprising a com,- pressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves when the pressure in said first con Y duit is above normal.

9. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a pressure responsive switch for closing said valves when the pressure in said first conduit is other than normal.

10. A refrigerating apparatus comprising a compressor, a condenser, evaporation means, means including a first conduit for supplying said evaporation means with liquid refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and meansincluding a pressure responsive switch for closing said valves when the pressure in said second conduit is below normal.

frigerant from said receiver, means including a 5 second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means including a float operated switch responsive to liquid conditions in said receiver for closing said valves.

12. A refrigerating apparatus comprising a compressor, a; condenser, a receiver, an auxiliary receiver, an evaporator, conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporator and said evaporator with said compressor,

a conduit connecting said receiver with said auxiliary receiver and means to regulate flow of fluid through said last mentioned conduit so as to limit the quantity of liquid in said receiver.

13. A refrigerating system comprising a com: pressor, a condenser, a receiver, an auxiliary receiver, evaporation means, conduits connecting said compressor with said condenser, said con- 5 denser with said receiver, said receiver with said evaporation means and said evaporation means with said compressor, a conduit connecting said receiver with said auxiliary receiver, means to regulate flow of fluid through said last mentioned conduit so as to limit the quantity of liquid in said receiver, electrically actuated valves for dividing said system into isolated sections and means including a float operated switch responsive to liquid conditions in said receiver for closing said valves.

14. A refrigerating system comprising a compressor, a condenser, a receiver, an auxiliary receiver, evaporation means, conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporation means and said evaporation means with said compressor, a conduit connecting said receiver with said auiiliary receiver, means to regulate fiow of fluid through said last men- 5 tioned conduit so as to limit the quantity of liquid in said receiver, electrically actuated valves for dividing said system into isolated sections and means including a pressure responsive switch for closing said valves when the pressure in said low side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a pressure responsive switch forclosing said magnetically ac- 5 tuated valves when a subnormal pressure exists in said system. i

16. A refrigerating system comprising a compressor, a condenser, a-plurality or evaporators. a low side header, means comprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each oi said branch conduits, return conduits connecting said evaporators with said low side header, a one-way valve in each of said return con- 1 duits, a magnetically actuated valve in said first mentioned conduit, a conduit connecting said low side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a pressure responsive switch for closing said magnetically actuated valves when a pressure above normal exists in said system.

17. A refrigerating system comprising a compressor, a condenser, a receiver, a plurality of evaporators, a low side header, means comprising a conduit and branch conduits connecting said condenser with said evaporators, a one-way valve in each of said branch conduits, return conduits connecting said evaporators with said low side header, a one-way valve in each of said return conduits, a magnetically actuated valve in said first mentioned conduit, a conduit connecting said low side header with said compressor, a magnetically actuated valve in said last mentioned conduit and means comprising a float actuated switch responsive to liquid conditions in said receiver for closing said valve.

18. A refrigerating system comprising a cornpressor, a condenser, a high side header, a plurality oi evaporators, a plurality 01 low side headers, a conduit connecting said condenser with said high side header, a magnetically actuated valve in said conduit, means comprising a plurality oi riser conduits each connected with a plurality of branch conduits for connecting said high side header with said evaporators, a one-way valve in each 01 said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporator with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprising a pressure responsive switch for closing all the aforesaid magnetically actuated valves when a subnormal pressure exists in said system.

19. A refrigerating system comprising a cornpressor, a condenser, a high side header, a plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side headers, a magnetically actuated valve in said conduit, means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said high side header with said evaporators, a one-way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporators with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprising a pressure responsive switch for closing all the aforesaid magnetically actuated valves when a pressure greater than normal exists in saidsystem.

20. A refrigerating system comprising a compressor, a condenser, a receiver, a high side header, a. plurality of evaporators, a plurality of low side headers, a conduit connecting said condenser with said high side headers, a magnetically actuated valve in said conduit, means comprising a plurality-oi riser conduits each con- 'nected with a plurality of branch conduits for connecting said high side header with said evaporators, a one-way valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting said evaporators with said low side headers, one-way valves in each of said return conduits, means comprising a main return conduit and branch conduits connecting said low side headers with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits, and means comprising a float actuated switch responsive to liquid conditions in "said receiver for closing all the aforesaid magnetically actuated 15 valves.

21. A refrigerating system comprising a plurality of evaporators, means for supplying refrigerant to said evaporators, said means comprising a header, a plurality of. riser conduits connected to said header and a plurality of branch conduits connecting each evaporator with one of said riser conduits, a valve in each of said riser conduits for preventing flow therethrough into said header and a valve in each of said branch 25 conduits for preventing flow therethrough into the respective riser conduits.

22.-An electrically operated refrigerating system comprising a compressor, a condenser, evaporation means, conduits connecting said compressor, condenser and evaporation means, valves in said conduits, and means for closing said valves to divide said system into isolated sec tions operable upon the failure of electric current for operating the system.

23. An electrically operated refrigerating system comprising a compressor, a condenser, an evaporator, nieans including a conduit for supplying said evaporator with liquid refrigerant from said condenser, acne-way valve in said 4 conduit adjacent said evaporator, means for conveying vaporous refrigerant from said evaporator to said compressor, a second valve in said conduit and means for closing said second valve upon the failure of electric current for operating 4 said system.

24. An electrically operated refrigerating system comprising a compressor, a condenser, evapoperation means, means inluding a first conduit for supplying said evaporation means with liquid 5 refrigerant from said condenser, means including a second conduit for conveying vaporous refrigerant from said evaporation means to said compressor, an electrically actuated valve in each of said conduits and means for closing said valves upon a failure otelectric current for operating said system.

25. An electrically operated refrigerating system comprising a compressor, a condenser, a receiver, an auxiliary receiver, evaporation means, 6 conduits connecting said compressor with said condenser, said condenser with said receiver, said receiver with said evaporation means and said evaporation means with said compressor, a conduit connecting said receiver with said aux- 6 iliary ,rece'iver, means to regulate flow of fluid through said last mentioned conduit so as to limit the quantity of liquid in said receiver, valves for dividing said system into isolated sections and means for closing said valves upon a failure of electric current for operating said system;

26. An electrically operated refrigerating system comprising a compressor, a condenser, a

magnetically actuated valves upon a failure of, v electric current for operating said system.

2'7. An electrically operated refrigerating sys tem comprising a compressor, a condenser, a high side header, a plurality of evaporator-s, a plurality of low side headers, a conduit connecting said condenser with said high side header, a magnetically actuated valve in said conduit, means comprising a plurality of riser conduits each connected with a plurality of branch conduits for connecting said high side header with said evaporators, a one-way -valve in each of said riser conduits, a one-way valve in each of said branch conduits, a plurality of return conduits connecting ,said evaporator with said low side headers, one-way valves in eachof said return conduits, means comprising a main return conduit and branch conduits connecting said low side headare with said compressor, a magnetically actuated valve in said main return conduit and in each of said last mentioned branch conduits and means for closing all the aforesaid magnetically actuated valves upon a failure, of electric current for operating said system.

28. That improvement in the art of refrigeration through the agency of an electrically operated refrigerating system which comprises producing an electromagnetic field with the electric current for operating the system and dividing the system into isolated sections upon decrease in strength of said field, below a predetermined value, m

29. A compressor, a condenser, and an evaporator connected to form a refrigerating system,

and automatic means for dividing the system into isolated sections operable upon a predetermined fall in liquid level in the high pressure side of the system.

30. A compressor, a condenser, and an evaporator connected to form a refrigerating system, and automatic means for stopping the compressor and for dividing the system into isolated sections operable upon a predetermined fall of the liquid level in the high pressure side of the system.

31. A compressor, a condenser, and an evaporator connected to form a refrigerating system,

and automatic means for stopping the compressor and for operating a signal operable upon a predetermined fall of the liquid level in the high pressure side of the system.

32. A compressor, a condenser, and an evaporator connected to form a refrigerating system.

and automatic means for dividing the system into isolated sections and for operating a signal oper-v able upon a predetermined fall of the liquid level in the high pressure side of the system.

33. A compressor, a condenser, and an evaporator connected to form a refrigerating system,

electrical means for supplying power to the system, and automatic means for dividing the fl systern into isolated sections operableupon a Ipredetermined fall in liquid leyel in high pressure side of the system.

' 34. That improvement in the art of refrigeration which comprises altering an electric circuit due to a predetermined fall in liquid level in the high pressure side of the system and dividing the system into isolated sections due to the alteration of said circuit.

,35. In (an electrically operated refrigerating 5 system means for producingan electromagnetic field, utilizing electric current for operating the system, means for dividing the system into isolated sections operative upon decrease in strength of said field below a predetermined value, and additional means for dividing the system into isolated sections upon a predetermined fall of liquid level in the high pressure side of the system.

36. In a refrigerating system employing electric current means for automatically dividing the 'system into isolated sections, and means responsive to a predetermined fall of liquid level in the high pressure side of the system for effecting said automatic division, and additional means operable upon the failure of electric current for dividing the system into isolated sections.

37. A compressor, a condenser, and an evaporator connected to form a refrigerating system,

a signal associated with said system, and automatic means for operating said signal, said automatic means being adapted to be actuated upon a predetermined loss of fluid from the high pressure side of the system.

a 38. A compressor, a condenser, and an evaporator connected to form a refrigerating system, a signal associated with said system, and automatic means for operating said signal, said automatic means being adapted to be actuated upon a predetermined loss of fluid from the system.

39. The improvement in the art of refrigera- 85 tion which comprises dividing a refrigerating system into isolated sections in response to a predetermined alteration of an electrical circuit forming a part of the system.

40. A refrigerating system including condensing and evaporating means connected in series, and means adapted to operate upon the occurrence of a leak in any portion of said system to subdivide the system into a number of isolated sections.

41. A refrigerating system comprising interconnected compressing, condensing and evaporating means, valves in said system, and means adapted to operate said valves upon the occurrence of a leak in any portion of said system for subdividing said system into a plurality of independently isolated sections whereby said leak will only permit the escape of refrigerant from the respective isolated section.

42. A refrigerating system comprising interconnected compressing, condensing and'evaporating means, valves in said system, and means adapted to operate said valves responsive to a predetermined loss of fluid from said system for subdividing the system into a plurality of independently isolated sections.

43. A refrigerating system comprising interconnected compressing, condensing and evaporating means, valves in said system, and means adapted to operate said valves responsive to either a predetermined loss of fluid from the system or in response to an abnormal drop in pressure resulting from a leak in the system for subdividing said system into a plurality of independently isolated sections.

4s. A refrigerating system comprising interconnected compressing. condensing and evaporating means, valves insaidsystem, and means change of liquid level for subdividing said system into a plurality 01', independent isolated sections.

45. A refrigerating system comprising evapo- 5 rating, condensing and other interconnected ele-' ments, valves in said system, and means adapted to operate said valves to subdivide said system into a plurality of independent sections and operable subject to any one of a number of conditions including loss of fluid, abnormal pressure change or abnormal liquid level change.

EDWARD T. WILLIAMS. 

